Mechanical telephone dialing instrument



Sept. 17, 1963 w. G. WHITNEY 3,104,286

MECHANICAL TELEPHONE DIALING INSTRUMENT Filed July 15, 1960 F I G. I

F l G. 2

INVENTOR. WILLIAM G. WHITNEY AGENT United States Patent ()fiFice 3,104,286 MECHANHIAL TELEPHONE DIALEJG INSTRUMENT William G. Whitney, Wayne, N..l., assignor to MeGraw- Edison Company, Elgin, IlL, a corporation of Dela- Ware Fiied July 15, 1960, Ser- No. 43,114 8 Claims. (ill. 179-90) This invention relates to a mechanical telephone dialing instrument and more particularly to a form of such instrument which will dial a prescribed telephone numbers responsive to a single manipulation.

An object of the invention is to provide an improved and simplified mechanism for operating a dial pulsing switch in accordance with a coded dialing member.

Another object is to provide a self-powered telephone dialing instrument which will dial a prescribed telephone number responsive merely to a manipulation to start the instrument running.

A further object is to provide such dialing instrument which is simple and economical to produce.

-A feature of the invention is in operating a switchpulsing cam through a one-revolution clutch which is controlled by direct mechanical coaction with a dialing member moved in synchronism with the clutch shaft and provided with a series of slots of different widths coded according to the number of dialing pulses to be produced to represent the respective letters and digits of the telephone number being dialed.

The present dialing instrument is intended especially for use in remote or isolated places where, for example, in case of emergency it is desired to dial a particular telephone number. An illustrative example of a particular use of the invention would be on an office elevator to enable the operator or passengers to dial a service department or station should the elevator become disabled between floors. In such applications the self-powered feature is an important one.

The foregoing objects and features of the invention will be apparent from the following description and the appended claims.

In the description of the invention reference is had to the accompanying drawings, of which:

FIGURE 1 is a fractional view partly in section of a dialing instrument illustrating the invention; and

FIGURE 2 is a cross sectional view taken on the line 2-2 of FIGURE 1.

The dialing instrument shown in the figures includes a rectangular frame or housing 10 formed as by casting. This housing has a bottom wall 11 provided with an upstanding flange at its front, left and back sides designated respectively as 12a, 12b and 120. The instrument is powered by a spring motor '13 having a cylindrical housing 14 mounted on a support arm 15 which is integral with the back wall 12c and which is disposed in a spaced overlapping relationship thereto. The motor comprises simply a spiral spring 16 secured at its outer end to the housing 14 and at its inner end to a shaft 17 which extends centrally through the end walls of the motor housing. On the outer end of the shaft 17 there is a key or finger piece 18 by which the spring 16 can be wound up to charge the motor. The inner end of the shaft extends onwardly through the support arm 15 and through the space between this arm and the back wall 120, and has a bearing 19 in the back wall. Journaled on this shaft in the space between the arm 15 and the back wall 12c is a spur gear 20. Secured to the shaft between the spur gear and the arm 15 is a small ratchet wheel 21. Pivoted at 22 to the side of the spur gear facing the ratchet wheel is a pawl 23 which engages the ratchet wheelunder pressure of a bias spring 24 (FIG- 3,l4,286 Patented Sept. 17, 1963 URE 2). This ratchet coupling between the shaft 17 and the spur gear permits the motor spring 16 to be wound by hand and retained in its charged condition until the dialing instrument is started since, as will appear, the spur gear 20 is normally in a latched condition.

Meshing with the spur gear 20 is a pinion gear 25 secured to a shaft 26 which is journaled in a bearing in the back wall 12a. The shaft 26 extends forwardly approximately half the distance through the space between the back and front walls 120 and 12a, and has a worm 27 secured to the forward end thereof which meshes with a gear 28 on a vertical shaft 29 of a dialling disk 30. The shaft 29 is journaled in a long bearing 31 secured to the bottom wall 11. Meshing in turn with the pinion gear 25 is a pinion gear 32 secured to a shaft 33 journaled in hearings in the front and back walls 12c and 12a. Adjacent to the back wall 12c on the shaft 33 is a gear 34 coupling the shaft to a suitable speed governor generally indicated at 35. Journaled on a central portion of the shaft 33 is a roller 36 having a radial pin or dog 37 which normally abuts against a rim portion of the dialing disk 39 to normally prevent the roller 36 from turning with the shaft 33. Also journaled on the shaft 33 near the forward end thereof is a one-lobe cam 38 for operating a pulsing switch 39 to be connected by lead wires 40 into a telephone line not shown. The roller 36 and cam 38 are confined on the shaft lengthwise thereof by stop collars 41. Secured at its ends to the roller 36 and cam 38 is a helical one-way clutch spring 42 wound tightly onto the shaft 33 in a direction such that when the roller 36 is held against rotating the frictional coupling between the shaft 33 and the clutch spring 42 will tend to unwind the spring and release it from the shaft causing the cam then to remain at standstill. However, the dialing disk 30 has a series of peripheral slots 43 to clear the dog 37 from the disk for predetermined intervals while the dialing instrument is running. During such intervals the roller 36 will turn with the shaft 33 and the clutch spring will grip the shaft under its own tension to clutch the cam 38 to the shaft. Therefore, during each release of the dog 37 from the dialing disk the cam 38 is driven through one or more full revolutions depending upon the width of the respective peripheral slots 43 in the dialing disk.

The dialing instrument is normally held from running by means of a latching bar 44 slidably mounted in a bearing 45 in the end Wall 1212. This latching bar projects under influence of a compression spring 46 into the path of a pin 47 on the dialing disk. Upon first winding the spring motor and then momentarily releasing the latching bar the motor will start driving the dialing disk 30 and the clutch shaft 33. The running of the instrument will continue for one full revolution of the dialing disk at which time it will be stopped by abutment of the pin 47 against the latching bar 44. During the running of the instrument the respective peripheral slots 43 in the dialing disk will pass the dog 37 and free the roller 36 to turn with the clutch shaft and cause the shaft to be coupled to the dial switch pulsing cam 38, the number of pulses produced during each passage of a slot 43 past the dog 37 depending upon the width of the respective slot. For any particular application a dialing disk is installed in the instrument having as many peripheral slots as there are letters and digits in the telephone number to be dialed, Also, the widths of the respective slots are coded according to the respective letters and digits of the telephone number. For example, to dial digit 1 the respective slot 43 will have only such width as will allow one passage of the dog 37 past the dialing disk. In other words, the slot in the dialing disk for dialing digit 1 need be only as wide as the dog plus a suitable practical clearance. To dial the digit 2 the respective 9 slot would have to have a greater width by the incremental distance of peripheral movement of the dialing disk during one revolution of the clutch shaft. For dialing 7 larger digits the width would be increased correspondingly. ,In theparticular example shown in FIGURE 1 the dialing disk is provided with seven peripheral slots for dialing a telephone number of seven letters and digits.

' Preferably, equal spaces are provided between successive peripheral slots to provide equal interdigital time intervals between successive pulses or pulse trains representing the respective letters and digits of the telephone number.

Although I have herein shown and described a dialing then momentarily releasing the start control 44. Further modifications will be apparent in the embodiment herein particularly shown and described to illustrate the invention Without departure from the scope thereof, which I endeavor to express according to the following claims.

I claim:

1. A telephone dialing instrument comprising a dial pulsing switch, rotatable means for pulsing said switch and means for intermittently operating said rotatable means according to a prescribed code comprising a driven shaft, a dog journalled on said shaft, a coil spring in frictional slidable engagement with said shaftand connected at one end to said dog and at the other end to said rotatable means, said spring being wound on said shaft in suchtdirection that said shaft tends to unwind the spring by its frictional engagement therewith when the shaft is turned and said dog is held from turning, and means for intermittently releasing said dog to cause the spring to instantly couple said shaft to said rotatable means comprising a dialing member having a path of intermittently driven by said shaft, said slots having variable predetermined widths coded according to the number of pulses to be produced to represent the respective letters and digits of 'the telephone number to be dialed.

2 A mechanical dialing instrument comprising a pulsing switch, a rotary cam for operating said pulsing switch, a' drive shaft, a friction clutch for coupling said shaft her, and means for driving said dialing member in fixed speed relationship to said shaft as the shaft is turned.

3. In a telephone dial mechanism: the combination of a pulsing switch, a drive shaft, a rotary cam for operating said switch, a dog journaled on said shaft, a friction coupling spring on said shaftrconnected between said dog and said carn, means for turning said drive shaft in a direction to cause the shaft by its frictional coupling with said spring to unwind the spring while said dog is held stationary and to cause said spring to grip said shaft to connect said cam to the shaft when said dog is released, a dialing member movable in 'a path traversing the path of said dog, and means for moving said dialing member at a speed in predetermined relationship to that of said shaft while said dog bears slidably against the dialing member responsive to the frictional coupling of said spring withsaid shaft, said dialing'member being provided with a series of transverse slots movable successively into registration with said dog by the movement of the dialing member to free said dog and cause said cam to be connected intermittently to said shaft, said slots being coded and causingrthereupon the same to be stopped when a a predetermined number of slots of said dialing member have traversed the path of said dog.

5. The drive set forth in claim 3 wherein said dialing member comprises a disk and said dog engages slidably to said cam, said clutch comprising a dog freely rotatably mounted on said shaft and a coil spring in frictional slidable engagement with said shaft and secured at one end to said dog and at'the other end to said cam, means for turning said shaft in a direction tending .to unwind said spring and free it from coupling engagement therewith when said dog: is held stationary and to cause the spring to grip the shaft and couple said cam thereto when the dog is free to turn with the shaft, a dialing member having a path of movement traversing the path of movement'said dog, said dog being in slidable engagement with said dialing member responsive to the frictional engagement of said spring with said shaft and said dialing member holding the dog normally from turning with said shaft, said dialing member having successive slots for clearing the dog of said dialing member, said slots having widths corresponding to the number of pulses to be produced to represent respective successive predetermined digits and letters of a telephone number to be dialed, said slots being spaced from each other by distances to provide predetermined interdigital time intervals between successive pulse trains representing the letters and digits of the telephonenuma rim portion of the disk, said disk having a series of open ended peripheral slots for causing the dog to be released to turn with said shaft intermittently as the disk is ro tated.

6. The drive set forth in claim 5 including motor means for rotating said disk and shaft, and start-stop means for said motor means including means effective upon each starting of the motor means to thereafter stop the motor means upon completion of one full revolution of said dialing disk.

7. A mechanical single-number telephone dialing instrument comprising a pulsing switch, a' rotary cam for operating said switch, a drive shaft, a clutch for connectingfsaid shaft to said cam including a dog journaled on said shaft and a helical spring frictionally gripping the shaft and connected at one end to said dog and at the other end to said cam, motor means for. driving said shaft in .a direction tending to unwind said spring When said dog is held stationary and causing said springtresponsive to its frictional engagement with said shaft to couple a said shaft to the cam when said dog is free to turn with the shaft, a dialing disk driven by said motor means in a path traversing the path of said dog, said dog being in slidable engagement with a rim portion of said disk under influence of the frictional coupling between the shaft and the spring with the dog being held stationary by the disk to preventthe cam from being driven by said shaft, said disk having a series of peripheral slots for intermittently clearing the disk of said dog to allow the dog to turn with said shaft by one or more full revolutions depending upon the width of the respective slots whereby to intermittently couple said cam to said shaft to produce successive pulse trains, each of said slots being separated from its adjacent slot by a predetermined dissaid 'motor means comprises a spring motor having 21 permanent drive coupling to both said disk and said shaft, 7

means for winding said spring motor, and a latch for saiddisk comprising a pawl and a single cooperating.

catch on said disk, means biasing said pawlinto engage- References Cited in the file of this patent UNITED STATES PATENTS Sengebusch July 30, 1940 Beltrami Ian. 30, 1945 McKellen Jan. 3, 1956 Goldschmidt June 9, 1959 

1. A TELEPHONE DIALING INSTRUMENT COMPRISING A DIAL PULSING SWITCH, ROTATABLE MEANS FOR PULSING SAID SWITCH AND MEANS FOR INTERMITTENTLY OPERATING SAID ROTATABLE MEANS ACCORDING TO A PRESCRIBED CODE COMPRISING A DRIVEN SHAFT, A DOG JOURNALLED ON SAID SHAFT, A COIL SPRING IN FRICTIONAL SLIDABLE ENGAGEMENT WITH SAID SHAFT AND CONNECTED AT ONE END TO SAID DOG AND AT THE OTHER END TO SAID ROTATABLE MEANS, SAID SPRING BEING WOUND ON SAID SHAFT IN SUCH DIRECTION THAT SAID SHAFT TENDS TO UNWIND THE SPRING BY ITS FRICTIONAL ENGAGEMENT THEREWITH WHEN THE SHAFT IS TURNED AND SAID DOG IS HELD FROM TURNING, AND MEANS FOR INTERMITTENTLY RELEASING SAID DOG TO CAUSE THE SPRING TO INSTANTLY COUPLE SAID SHAFT TO SAID ROTATABLE MEANS COMPRISING A DIALING MEMBER HAVING A PATH OF MOVEMENT EXTENDING ALONG SAID SHAFT, MEANS FOR MOVING SAID DIALING MEMBER AS THE SHAFT IS TURNED, SAID DOG BEING IN SLIDABLE ENGAGEMENT WITH SAID DIALING MEMBER RESPONSIVE TO THE TURNING OF SAID SHAFT, AND A SERIES OF SLOTS IN SAID DIALING MEMBER CORRESPONDING TO RESPECTIVE LETTERS AND DIGITS OF A TELEPHONE NUMBER TO BE DIALED FOR INTERMITTENTLY RELEASING SAID DOG FROM SAID DIALING MEMBER AND CAUSING SAID ROTATABLE MEANS TO BE CORRESPONDINGLY INTERMITTENTLY DRIVEN BY SAID SHAFT, SAID SLOTS HAVING VARIABLE PREDETERMINED WIDTHS CODED ACCORDING TO THE NUMBER OF PULSES TO BE PRODUCED TO REPRESENT THE RESPECTIVE LETTERS AND DIGITS OF THE TELEPHONE NUMBER TO BE DIALED. 